User:Hog Farm/Siege of Vicksburg

The siege of Vicksburg (May 18 – July 4, 1863) was the final major military action in the Vicksburg campaign of the American Civil War. In a series of maneuvers, Union Maj. Gen. Ulysses S. Grant and his Army of the Tennessee crossed the Mississippi River and drove the Confederate Army of Mississippi, led by Lt. Gen. John C. Pemberton, into the defensive lines surrounding the fortress city of Vicksburg, Mississippi.

Vicksburg was the last major Confederate stronghold on the Mississippi River; therefore, capturing it completed the second part of the Northern strategy, the Anaconda Plan. When two major assaults against the Confederate fortifications, on May 19 and 22, were repulsed with heavy casualties, Grant decided to besiege the city beginning on May 25. After holding out for more than forty days, with their supplies nearly gone, the garrison surrendered on July 4. The successful ending of the Vicksburg campaign significantly degraded the ability of the Confederacy to maintain its war effort. This action, combined with the surrender of the down-river Port Hudson to Maj. Gen. Nathaniel P. Banks on July 9, yielded command of the Mississippi River to the Union forces, who would hold it for the rest of the conflict.

The Confederate surrender on July 4, 1863, is sometimes considered, when combined with Gen. Robert E. Lee's defeat at Gettysburg by Maj. Gen. George Meade the previous day, the turning point of the war. It cut off the Trans-Mississippi Department (containing the states of Arkansas, Texas and part of Louisiana) from the rest of the Confederate States, effectively splitting the Confederacy in two for the rest of the war. Lincoln called Vicksburg "the key to the war."

Outbreak of war and the importance of the Mississippi
During the early 19th century, a large cultural divide grew between the Northern United States and the Southern United States, with slavery being a major issue. Northerner Abraham Lincoln won the 1860 United States presidential election, and with the more populous north holding the balance of political power, many southerners decided that secession was the only way to preserve slavery. On December 20, 1860, the state of South Carolina seceded, followed by other Deep South states in early 1861. By February 4, seven states had seceded, and on that day the seceding states formed the Confederate States of America. On the morning of April 12, Confederate forces opened fire on Fort Sumter, in South Carolina, beginning the war.

Shortly after Fort Sumter, Lincoln called for 75,000 volunteers to put down the Confederacy, leading to four more states seceding and joining the Confederacy. Early in the war, Commanding General of the United States Army Winfield Scott suggested the Anaconda Plan to defeat the Confederates. The basis of the plan was to control the Mississippi River and implement the Union blockade, cutting the Confederacy off from external trade. This plan was not formally adopted by the United States (known as the Union during the war), although elements of it largely foreshadowed eventual Union policy. Union control of the Mississippi would divide the Confederacy into two sections, while Confederate control of the river stifled Union trade.

1862 campaigns for Vicksburg
In early 1862, Union forced captured New Orleans, Louisiana, which combined with a number of victories, gave the Union control of much of the Mississippi Valley. Vicksburg, Mississippi, became the key Confederate stronghold on the Mississippi River. In May, Union Navy vessels moved upriver from New Orleans and began bombarding Vicksburg; they later ran upstream past the batteries at Vicksburg and on June 28 joined a naval force that had come down from Memphis, Tennessee. The Union ships continued to shell the Confederate positions at Vicksburg, but never landed an infantry force to assault the city. Realizing that the city could not be taken by naval power alone, the Union vessels withdrew in late July; Vicksburg had been under fire for 67 days. In August, the Confederate occupied and began fortifying Port Hudson, Louisiana, creating a second Confederate stronghold on the river. Holding both points gave the Confederate access to the mouth of the Red River of the South and a lifeline to the Trans-Mississippi.

In late 1862, Union troops began a two-pronged advance against Vicksburg from the north. In late November, about 40,000 men commanded by Major General Ulysses S. Grant moved from Tennessee towards the city, but Confederate cavalry wrecked Grant's supply lines, forcing Grant to withdraw. Unaware that Grant had withdrawn, the other prong of the Union advance, commanded by Major General William T. Sherman, left Memphis on December 20 and traveled downriver via ship. Sherman's force skirmished with Confederate troops before launching a major attack on December 29, in the Battle of Chickasaw Bayou. The assault was repulsed, and Sherman's men left the area on January 1, 1863.

Military situation


After Sherman's failure at Chickasaw Bluff, Grant reformed his army to again fight against Vicksburg, taking personal command of the campaign on January 30. His forces made several attempts to produce alternate routes to Vicksburg or to bypass the city. Canal attempts such as Grant's Canal failed, as did two attempts to navigate through various waterways and approach Vicksburg from the north: the Yazoo Pass Expedition and the Steele's Bayou Expedition. At the end of March, Grant sent a force down the Louisiana side of the Mississippi River, across from Vicksburg, and Union Navy ships ran past the Confederate batteries in mid-April. By the end of April, Grant had a substantial force at Hard Times, Louisiana. The intention was for Union Navy ships to batter the Confederate defenses across the river at Grand Gulf, Mississippi, into submission and then cross troops over. On April 29, the Union Navy failed to silence the Confederate batteries in the Battle of Grand Gulf, but Grant moved his men further downriver and brought them across the Mississippi River at Bruinsburg, Mississippi, the next day.

Moving inland, the Union troops pushed aside a Confederate blocking force in the Battle of Port Gibson on May 1. Grant decided to move his troops eastwards and then turn back west towards Vicksburg, as that plan provided a good chance of both taking the city and trapping the Confederate army there, which was commanded by Lieutenant General John C. Pemberton. After part of the Union army collided with and defeated Confederate troops in the Battle of Raymond on May 12, he decided to aim his troops for the city of Jackson. Pemberton had wanted to pull most of the men from the defenses of Port Hudson in order to concentrate his forces, but Confederate president Jefferson Davis objected to the proposed temporary abandonment of Port Hudson and declared that both points should be held. Davis also sent General Joseph E. Johnston to cooperate with Davis.

Pemberton had his army between Vicksburg and Jackson, while Johnston arrived at the latter point on May 13. Despite Grant not using a direct supply line at this time, Pemberton moved his men south to try to cut the Union supply line, believing that it existed. At Jackson, Johnston believed it was too late and withdrew from the city in the face of a Union attack. After the fall of Jackson, Johnston sent Pemberton a message suggesting that Pemberton advance his force against Grant, with Johnston to attack from the other direction. However, Johnston was at this time moving his men away from Pemberton's force. On May 16, Pemberton ceased the attempt to cut Grant's supply line, and shifted his force into a position between Grant and Vicksburg. That day, Union forces attacked Pemberton in the Battle of Champion Hill. After hard fighting, the Confederates were forced to withdraw back towards Vicksburg; any chance of a conjunction between Pemberton and Johnston was ended. An attempt to buy time for a cut-off Confederate division to rejoin Pemberton's army ended in a rout the next day at the Battle of Big Black River Bridge, and on May 18 the Union troops reached the Vicksburg area. That same day, Union troops also occuppied a position at Haynes Bluff that allowed them to open a supply link to Union transports in the Yazoo River. Caught between Johnston's belief that Vicksburg was worthless militarily, and Davis's belief that the city should be held, Pemberton had acted indecisively and had brought his army into Vicksburg, where they were now trapped.

Fortifications
The Confederates had begun fortifying Vicksburg in late 1862 and early 1863, and by the time Grant's men arrived at the city, a ring of fortifications with both flanks anchored on the Mississippi River defended the town. The fortifications began on the river at a point north of the city, ran roughly eastward, and then turned to the southwest, after which it turned back towards the river, ending at the river 2 miles below the city. The semicircle of defensive works ran for a total of about 8 miles. Further artillery batteries face the river. The height of the terrain around Vicksburg varied, with the highest point being 400 ft above sea level. Defensive works were constructed on the high ground. The fortifications had been made from loess soil, and deterioration and the failure to reinforce the defenses with logs meant that the Confederates had to improve parts of the positions.

The Confederate works included nine major forts. These forts were a mixture of redans, lunettes, and an enclosed redoubt. Beginning on the north of the Confederate line along the road to Yazoo City was Fort Hill. Where the line turned south was the Stockade Redan complex, which was intersected by the Graveyard Road. This complex consisted of the Stockade Redan south of the road, the 27th Louisiana Lunette north of the road, and a wooden stockade between. About 1 mile south of the Stockade Redan complex the Jackson Road passed through the fortifications. North of the road was the 3rd Louisiana Redan, while Great Redoubt was to the south. Great Redoubt was considered to be the strongest of the Confederate forts. About another mile south was a railroad and the Baldwin Ferry Road. The road was covered by the 2nd Texas Lunette, while the railroad was defended by the Railroad Redoubt. Located 0.5 miles of the Railroad Redoubt was a work known as the Square Fort, and another mile further along the defenses was the Salient Work, which covered the Hall's Ferry Road. Another 1.75 miles later, the South Fort held the other Confederate flank. At various points along the line, trees had been felled to form abatis. The defenses also incorporated breastworks and rifle pits. Supporting these lines were 128 cannons.

Union
At the beginning of the siege, Grant's army consisted of the XIII Corps, commanded by Major General John A. McClernand; the XV Corps, commanded by Major General William T. Sherman; and the XVII Corps, commanded by Major General James B. McPherson. At this time, the Union forces numbered about 45,000 men. Grant continued to receive reinforcement throughout June, including 8,000 men from the IX Corps, commanded by Major General John Parke, and a detachment from the XVI Corps that was operationally assigned to the XIII Corps. A force from the Department of Missouri commanded by Major General Francis J. Herron arrived on June 13. By June 17, Grant had a total strength at that time of 77,000 men. The next day, McClernand was removed from command, and was replaced by Major General E. O. C. Ord.

Confederate
During the siege, Pemberton commanded four divisions, which were commanded by Major Generals Carter L. Stevenson, John H. Forney, Martin L. Smith, and John S. Bowen. Not attached to any of the divisions were the artillery batteries facing the Mississippi River, as well as a few miscellaneous units: a detachment of the Signal Corps, a force of City Guards, and portions of two infantry regiments. At the beginning of the siege, Pemberton could muster about 30,000 Confederate soldiers. Another division commanded by Major General William W. Loring had served with Pemberton earlier in the campaign, but retreated via a different route after the fighting at Champion Hill and went to Jackson instead of Vicksburg. Johnston gathered over 30,000 men at Canton, known as the Army of Relief, for the purpose of relieving Vicksburg, but his command did not leave Canton until July 1 and made it no closer to Vicksburg than the Big Black River before the city fell. In early June, Confederate forces in the Trans-Mississippi Department were used unsuccessfully to interfere with Grant's siege, and a further attempt to use Trans-Mississippi troops to break the siege by attacking Union positions in the Trans-Mississippi failed in the Battle of Helena.

May 19


After his army arrived around Vicksburg, Grant decided to order an assault on the city. A quick victory would be advantageous politically, as well as militarily. He believed that the Confederate troops were demoralized and that storming the Confederate lines would be successful as a result. Additionally, he was concerned about the morale of his own being decreased by what his soldiers might see as an unnecessary siege, and a siege would both give Johnston a chance to intervene and would also require Grant to request additional reinforcements, which could be better used elsewhere if Vicksburg was taken quickly. Sherman's corps was positioned on the Union right, McPherson was in the center, and McClernand on the Union left. Some skirmishing occurred on May 18 as Sherman moved into position. Grant's orders were for three salvos of cannon fire to be shot at 2:00 pm on May 19, signaling to the three corps commanders to begin the all-out assault. At 2:00 pm, the cannon shots were fired, but only Sherman's corps was in position at this time. McClernand and McPherson's men would have to cover more ground, some of it over very rough terrain, for their assaults, leading to an uncoordinated attack.

McClernand's men were slowed by crossing 800 yd of rough terrain before reaching the Confederate works. Confederate fire and the terrain disorganized their lines, with the left portion of McClernand's line being in a particularly great state of disorder. One of the Union brigade commanders, Brigadier General Albert L. Lee was wounded in the neck during the attack. McClernand ordered an end to the attack at around dark, The men took up a position 400 yds from the Confederate line, and six cannons from the 7th Michigan Battery were brought forward in support. Likewise, McPherson's corps did not produce an attack that was coordinated or at full strength. The divisions of Brigadier General Isaac F. Quinby and Major General John A. Logan were barely engaged. The brigade of Brigadier General Thomas E. G. Ransom attacked the 3rd Louisiana Redan. Ransom's attack was disrupted when the 17th Wisconsin Infantry Regiment charged too early, and with both flanks unsupported, Ransom's men halted and were pinned down before reaching the Confederate lines.

Much of Sherman's corps engaged only in skirmishing that day, with Brigadier General John M. Thayer's brigade involved in particularly heavy skirmishing. Battery F, 2nd Missouri Light Artillery was able to take a position that forced the evacuation of a Confederate battery (the battery was reoccupied the next day after improvements to its defenses) and also covered one of the roads that the Confederates could have used to escape Vicksburg. Sherman's main attack struck one of the strongest positions on the Confederate line, the Stockade Redan. Pemberton had expected trouble in the area and reinforced the defenses with Colonel Francis M. Cockrell's First Missouri Brigade. For Sherman, Major General Francis Preston Blair Jr.'s division made the assault. Expecting the Confederates to quickly cave in, many Union officers had not brought scaling ladders for their men. Colonel Thomas Kilby Smith's brigade was pinned down under heavy fire, and Colonel Giles A. Smith's brigade was repulsed, with some of its units suffering heavy casualties after being caught in a crossfire. Brigadier General Hugh Ewing's brigade charged the 27th Louisiana Lunette, but half of the brigade was caught in bad terrain and did not make it to the Confederate line, while the rest was repulsed. Blair's men maintained a position in front of the Confederate works, but began to run low on ammunition. Many Union troops were trapped in no man's land, and remained under fire from the Confederates, who threw hand grenades and lit artillery shells into the Union positions. Most of the trapped Union troops were able to escape under cover of darkness.

The attacks had accomplished little. Grant's army suffered 942 casualties during the assaults, of which 613 were in Blair's division. Union troops were discouraged by the repulse, which also increased Confederate morale. Historian Ed Bearss estimated Confederate losses at about 200. Grant still believed that an attack could lead to a quick victory, which would reduce the threat that Grant believed Johnston posed, and would also free up some of Grant's troops for action in the Port Hudson campaign. With some hesitation, and the support of Sherman, McClernand, and McPherson, Grant decided to make another attack, this time with better preparations and with a greater proportion of his troops involved. Both Grant and Pemberton were surprised by the stiffness of the Confederate defense.

May 22


Grant's men spent the next two days working their way into positions closer to the Confederate lines, in order to decrease the distance they would have to charge over. Union artillery and skirmisher fire reached heavy proportions. Union artillery caused some damage to the Confederate defenses, which the Confederates then had to spend time repairing. Grant also sent a brigade to the Confederate far right, which he had previously not kept closely blocked, in order keep Confederate troops there pinned down during the coming attack. With his troops in position, artillery emplaced, and the Navy instructed to bombard the Confederate positions along the river and at South Fort, Grant was ready for the attack, which was to take place at 10:00 am on May 22. The Union officers synchronized their watches with Grant's, a procedure that had not yet been common in the war.

Beginning at about 6:00 am, a four-hour preparatory bombardment of the Confederate positions was made. In Blair's division, an approximately 150-man forlorn hope detachment composed of volunteers was assembled to lead the assault. Expecting an attack, the Confederates heavily reinforced the Stockade Redan area, again utilizing Cockrell's troops. In Sherman's sector, at roughly the called-upon time, the forlorn hope charged, followed by the rest of Blair's division. Union artillery provided supporting fire during the assault, but began to run low on ammunition and would not receive more until the afternoon.

The Confederate held their fire until the forlorn hope was close to their lines, and then opened with an effective volley. The forlorn hope was halted by the Confederate fire. Still, many of them had reached the Stockade redan's parapet, and had brought boards to plank the ditch in front of the position. Blair's troops entered the action and were repulsed, but Tuttle's division remained to the rear waiting for a signal that it was their turn to attack, and Steele's men spent the morning attempting to deploy via a ravine. Steele's line was lengthy, while those of Blair and Tuttle had been compact, and Steele also had to deal with some of the worst terrain on the entire battlefield. Not until the afternoon would that division be in position.

In McPherson's sector, Ransom moved his troops to within 100 yd of the Confederate lines, but then halted, awaiting support, as his flank would have been badly exposed if he advanced. Further to the left, Logan's division was tasked with taking the 3rd Louisiana Redan and Great Redoubt. Two of his brigades – those commanded by Brigadier Generals John Eugene Smith and John Dunlap Stevenson – would charge, while the third remained in reserve. Smith's attack failed within minutes, while Stevenson was able to use the terrain to his advantage during the approach stage of the assault. Union artillery fire mostly silenced the Confederate cannon in the Great Redoubt, but Stevenson pulled back after two of his regiments suffered heavy casualties during the attack; the brigade had also found that the scaling ladders given them were too short. McPherson's final division, commanded by Brigadier General Isaac Quinby, was in position to attack the portion of the Confederate line held by Brigadier General John Creed Moore's brigade. Quinby's division did not make an assault: one of the brigade commanders stated that the position was too strong to take. Quinby sent the brigade reinforcements, but the attack was not ordered.

In McClernand's sector, Brigadier General Eugene A. Carr's division was to take the Railroad Redoubt and the 2nd Texas Lunette, while that of Brigadier General Peter J. Osterhaus was to move against the Square Fort. Brigadier General Andrew Jackson Smith's division supported Carr, but Carr and Smith were aligned in such a fashion that each had one brigade attack the Railroad Redoubt, and the other brigade attack the 2nd Texas Lunette. Brigadier General Michael K. Lawler's and Colonel William J. Landram's brigades attacked the Railroad Redoubt and drove the Confederates from the position, but were unable to fully capture the position. The attack on the 2nd Texas Lunette was led by Brigadier General William P. Benton's brigade. Part of the 18th Indiana Infantry Regiment gained the lunette's ditch, but the rest of the brigade was repulsed. Brigadier General Stephen G. Burbridge's brigade attacked in support of Benton, but the Confederates, reinforced by Waul's Legion, were able to stabilize the situation, and a stalemate developed at the 2nd Texas Lunette. Osterhaus attacked with two brigades: those of Colonels Daniel W. Lindsey, and James Keigwin, who was commanding in place of the wounded Lee. In support was the only brigade of Brigadier General Alvin P. Hovey's division on the field. Normally commanded by Brigadier General George F. McGinnis, it was under the command of Colonel William T. Spicely, as McGinnis was ill. Osterhaus's attack was repulsed, and Spicely's brigade never entered the action.

McClernand's dispatch
By 11:00 am, it was obvious that the Confederates would not be overrun by the assaults. Grant received a dispatch from McClernand, which stated that his men were heavily engaged, facing Confederate positions that were being reinforced, and that it was necessary for McPherson to attack on McClernand's right to divert Confederate attention. Grant responded with the mistaken claim that much of McClernand's force was not heavily engaged, and that McClernand should use his own reserves. Another message from McClernand, this one written at noon, reached Grant. In it, McClernand misleading claimed to have captured parts of two Confederate forts. Grant showed the message to Sherman, who decided to make another assault, and after 1:00 pm, Grant received another message from McClernand, which claimed to have captured the Confederate earthworks at several points. Doubting McClernand's claims but lacking the time to personally investigate that section of his line, at 2:00 pm, Grant ordered McPherson to use Quinby's division to support McClernand.

At around 2:00 pm, Sherman ordered the brigades of Ransom and Giles Smith to attack, but the Union troops were repulsed easily. About an hour later, Sherman decided to attack with Tuttle's division. Historian Michael B. Ballard suggests that this final attack by Sherman may have been done simply because Sherman's pride would not allow him to be outperformed by McClernand. Brigadier General Joseph A. Mower's brigade was repulsed, and Sherman then called the attack off. Tuttle's other two brigades did not make the attack. Steele's division finally charged at about 4:00 pm. The two front brigades were repulsed, although a few men reached the ditch in front of the 26th Louisiana Redoubt, and that attack fizzled out.

In McPherson's zone, at about 2:00 pm, Logan's division made another attack against the Confederate positions. Smith's brigade led the attack, but Smith called off the thrust once his lead regiment, the 45th Illinois Infantry Regiment, was repulsed. Quinby's division was sent south to McClernand to exploit the area of the claimed breakthrough. Colonel John B. Sanborn's brigade moved up in support of Burbridge, but Burbridge assumed his men were being replaced by Sanborn's and withdrew. Seeing this, Confederate Brigadier General Martin E. Green sortied with two dismounted cavalry units, blunting Sanborn's attack and stabilizing the situation. At around 4:30 pm, Colonel George B. Boomer's brigade advanced, but became disorganized and halted to reform. During Boomer's halt, the Confederates were able to drive McClernand's men from the Railroad Redoubt, and Boomer was killed when his brigade assaulted. Osterhaus cancelled an assault involving Quinby's third brigade due to darkness. In the vicinity of South Fort, Brigadier General John McArthur's brigade accomplished little throughout the day.

Grant lost 502 men killed, 2,550 wounded, and 147 men missing during the day's attacks, compared to about 500 losses from all causes for the Confederates. About 40,000 Union soldiers had been involved in the fighting, while only about half of Pemberton's 28,000 Confederates had been. Grant blamed the additional casualties from the afternoon round of assaults on McClernand's misleading dispatch. A truce was called late on May 25 to bury the Union dead and recover the wounded.

Siege operations


Historian Shelby Foote wrote that Grant "did not regret having made the assaults; he only regretted that they had failed." Grant reluctantly settled into a siege. On May 25, Lt. Col. John A. Rawlins issued Special Orders No. 140 for Grant: "Corps Commanders will immediately commence the work of reducing the enemy by regular approaches. It is desirable that no more loss of life shall be sustained in the reduction of Vicksburg, and the capture of the Garrison. Every advantage will be taken of the natural inequalities of the ground to gain positions from which to start mines, trenches, or advance batteries. ..." Grant wrote in his memoirs, "I now determined upon a regular siege—to 'out-camp the enemy,' as it were, and to incur no more losses."

Federal troops began to dig in, constructing elaborate entrenchments which the soldiers of the time referred to as "ditches". These surrounded the city and moved steadily closer to the Confederate fortifications. With their backs against the Mississippi and Union gunboats firing from the river, Confederate soldiers and citizens alike were trapped. Pemberton was determined to hold his few miles of the Mississippi as long as possible, hoping for relief from Johnston or elsewhere.

A new problem confronted the Confederates. The dead and wounded of Grant's army lay in the heat of Mississippi summer, the odor of the deceased men and horses fouling the air, the wounded crying for medical help and water. Grant first refused a request of truce, thinking it a show of weakness. Finally he relented, and the Confederates held their fire while the Union recovered the wounded and dead on May 25, soldiers from both sides mingling and trading as if no hostilities existed for the moment.

After this truce, Grant's army began to fill the 12 mi ring around Vicksburg. It soon became clear that even 50,000 Union soldiers would not be able to effect a complete encirclement of the Confederate defenses. Pemberton's outlook on escape was pessimistic, but there were still roads leading south out of Vicksburg unguarded by Union troops. Grant sought help from Maj. Gen. Henry W. Halleck, the Union general-in-chief. Halleck quickly began to shift Union troops in the West to meet Grant's needs. The first of these reinforcements was a 5,000-man division from the Department of the Missouri under Maj. Gen. Francis J. Herron on June 11. Herron's troops, remnants of the Army of the Frontier, were attached to McPherson's corps and took up position on the far south. Next came a three division detachment from XVI Corps led by Brig. Gen. Cadwallader C. Washburn on June 12, assembled from troops at the nearby posts of Corinth, Memphis, and LaGrange. The final significant group of reinforcements to join was the 8,000-man strong IX Corps from the Department of the Ohio, led by Maj. Gen. John G. Parke, arriving on June 14. With the arrival of Parke, Grant had 77,000 men around Vicksburg.

In an effort to cut Grant's supply line, Confederates in Louisiana under Major General John G. Walker attacked Milliken's Bend up the Mississippi on June 7. This was largely defended by recently enlisted United States colored troops. Despite having inferior weaponry, they fought bravely and repulsed the Confederates with help from gunboats, although at heavy cost; the defenders lost 652 to the Confederate 185. The loss at Milliken's Bend left the Confederates with no hope for relief other than from the cautious Johnston.

Pemberton was boxed in with plentiful munitions but little food. The poor diet was telling on the Confederate soldiers. By the end of June, half were sick or hospitalized. Scurvy, malaria, dysentery, diarrhea, and other diseases cut their ranks. At least one city resident had to stay up at night to keep starving soldiers out of his vegetable garden. The constant shelling did not bother him as much as the loss of his food. As the siege wore on, fewer and fewer horses, mules, and dogs were seen wandering about Vicksburg. Shoe leather became a last resort of sustenance for many adults.

During the siege, Union gunboats lobbed over 22,000 shells into the town and army artillery fire was even heavier. As the barrages continued, suitable housing in Vicksburg was reduced to a minimum. A ridge, located between the main town and the rebel defense line, provided lodging for the duration. Over 500 caves, known locally as "bombproofs", were dug into the yellow clay hills of Vicksburg. Whether houses were structurally sound or not, it was deemed safer to occupy these dugouts. People did their best to make them comfortable, with rugs, furniture, and pictures. They tried to time their movements and foraging with the rhythm of the cannonade, sometimes unsuccessfully. Because of the citizens' burrowing, the Union soldiers gave the town the nickname of "Prairie Dog Village". Despite the ferocity of the Union fire, fewer than a dozen civilians are known to have been killed during the siege.

Command changes
One of Grant's actions during the siege was to settle a lingering rivalry. On May 30, General McClernand wrote a self-adulatory note to his troops, claiming much of the credit for the soon-to-be victory. Grant had been waiting six months for him to slip, ever since they clashed early in the campaign, around the Battle of Arkansas Post. He had received permission to relieve McClernand in January 1863 but waited for an unequivocal provocation; McClernand was relieved on June 18. Grant so carefully prepared his action that McClernand was left without recourse. McClernand's XIII Corps was turned over to Maj. Gen. Edward Ord, who had recovered from an October 1862 wound sustained at Hatchie's Bridge. In May 1864, McClernand would be given a command in a remote area of Texas.

Another command change occurred on June 22. In addition to Pemberton in Vicksburg, Grant had to be aware of Confederate forces in his rear under the command of Joseph E. Johnston. He stationed one division in the vicinity of the Big Black River Bridge and another reconnoitered as far north as Mechanicsburg; both acted as covering forces. By June 10, the IX Corps, under Maj. Gen. John G. Parke, was transferred to Grant's command. This corps became the nucleus of a special task force whose mission was to prevent Johnston, who was gathering his forces at Canton, from interfering with the siege. Sherman was given command of this task force and Brig. Gen. Frederick Steele replaced him at XV Corps. Johnston eventually began moving to relieve Pemberton and reached the Big Black River on July 1, but he delayed a potentially difficult encounter with Sherman until it was too late for the Vicksburg garrison, and then fell back to Jackson. Sherman would pursue Johnston and recapture Jackson on July 17.

Louisiana operations


Throughout the siege Union and Confederate forces kept busy in a supporting role on the Louisiana side of the Mississippi River. Lt. Gen. Edmund Kirby Smith, commander of the Trans-Mississippi Department, received a telegraph from Pemberton on May 9 requesting that he move against Grant's communication lines along the Mississippi River. Grant had established important supply depots at Milliken's Bend, Young's Point, and Lake Providence, all within Smith's jurisdiction, but Smith failed to recognize the importance of Pemberton's situation. It was not until June when Smith finally took action on Pemberton's request, directing Maj. Gen. Richard Taylor to "do something" in support of the Vicksburg garrison. Taylor commanded the District of Western Louisiana and developed a three-pronged campaign against Grant's three supply depots. All three of Taylor's assaults were defeated at the Battle of Milliken's Bend, the Battle of Young's Point, and the Battle of Lake Providence.

In response to the growing Confederate activity in the area, Grant decided to dispatch troops from the Vicksburg trenches across the river. The presence of Maj. Gen. John G. Walker's Confederate division on the Louisiana side was of particular concern; its presence could possibly aid any Confederate attempt to escape from Vicksburg. Therefore, Brig. Gen. Alfred W. Ellet's Mississippi Marine Brigade and Joseph A. Mower's brigade from Sherman's corps were ordered to the vicinity of Milliken's Bend. Mower and Ellet were to cooperate against Walker's division, which was stationed in the vicinity of Richmond, Louisiana. Richmond was also an important supply line providing Vicksburg with food from Louisiana. On June 15, Ellet and Mower defeated Walker and destroyed Richmond.

Ellet's men returned to De Soto Point and constructed an artillery battery targeting an iron foundry recasting spent Union artillery shells. Construction was begun on June 19, which placed a 20-pounder Parrott rifle in a casemate of railroad iron. The targeted foundry was destroyed on June 25 and the next day a second Parrott gun was added to the battery, which continued to harass the defenders until the garrison's surrender.

Additional Confederate activity in Louisiana occurred on June 29 at Goodrich's Landing when they attacked a plantation and an army training center run by former slaves. The Confederates destroyed the plantations and captured over a hundred former slaves before disengaging in the face of Ellet's Marines. Confederate raids such as these were disruptive and caused damage, but they were only minor setbacks and demonstrated that the Confederates could cause only momentary disturbances in the area.

Crater at the Third Louisiana Redan


Late in the siege, Union troops tunneled under the 3rd Louisiana Redan and packed the mine with 2,200 pounds of gunpowder. The explosion blew apart the Confederate lines on June 25, while an infantry attack made by troops from Logan's XVII Corps division followed the blast. The 45th Illinois Regiment (known as the "Lead Mine Regiment"), under Col. Jasper A. Maltby, charged into the 40 ft diameter, 12 ft deep crater with ease, but were stopped by recovering Confederate infantry. The Union soldiers became pinned down and the defenders rolled artillery shells with short fuses into the pit with deadly results. Union engineers worked to set up a casemate in the crater in order to extricate the infantry, and soon the soldiers fell back to a new defensive line. From the crater left by the explosion, Union miners worked to dig a new mine to the south. On July 1, this mine was detonated but no infantry attack followed. Pioneers worked throughout July 2 and 3 to widen the initial crater to be large enough for an infantry column of four to pass through for any future assault. However, events the following day negated the need for any further assaults.

Capture


On July 3, Pemberton sent a note to Grant regarding the possibility of negotiations for peace. Grant, as he had done at Fort Donelson, first demanded unconditional surrender. He then reconsidered, not wanting to feed 30,000 Confederates in Union prison camps, and offered to parole all prisoners. Considering their destitute and starving state, he never expected them to fight again; he hoped they would carry home the stigma of defeat to the rest of the Confederacy. In any event, shipping that many prisoners north would have occupied his army and taken months. Pemberton officially surrendered his army on July 4. Most of the men who were paroled on July 6 were exchanged and received back into the Confederate Army on August 4, 1863, at Mobile Harbor, Alabama. They were back in Chattanooga, Tennessee, by September and some fought in the Battles for Chattanooga in November and against Sherman's invasion of Georgia in May 1864. The Confederate government protested the validity of the paroles on technical grounds and the issue was referred to Grant who, in April 1864, was general in chief of the army. The dispute effectively ended all further prisoner exchanges during the war except for hardship cases.

Surrender was formalized by an old oak tree, "made historical by the event". In his Personal Memoirs, Grant described the fate of this luckless tree:

"It was but a short time before the last vestige of its body, root and limb had disappeared, the fragments taken as trophies. Since then the same tree has furnished as many cords of wood, in the shape of trophies, as the 'True Cross'."

The surrender was finalized on July 4, Independence Day, a day Pemberton had hoped would bring more sympathetic terms from the United States. Although the Vicksburg campaign continued with some minor actions, the fortress city had fallen and, with the surrender of Port Hudson on July 9, the Mississippi River was firmly in Union hands and the Confederacy split in two. President Lincoln famously announced, "The Father of Waters again goes unvexed to the sea."

Union casualties for the battle and siege of Vicksburg were 4,835; Confederate were 32,697, of whom 29,495 had surrendered. The full campaign, since March 29, claimed 10,142 Union and 9,091 Confederate killed and wounded. In addition to the men under his command, Pemberton turned over to Grant 172 cannons and 50,000 rifles.

Aftermath
Vicksburg was the last major Confederate stronghold on the Mississippi River; therefore, capturing it completed the second part of the Northern strategy, the Anaconda Plan. The successful ending of the Vicksburg campaign significantly degraded the ability of the Confederacy to maintain its war effort. This action, combined with the surrender of Port Hudson to Maj. Gen. Nathaniel P. Banks on July 9, yielded command of the Mississippi River to the Union forces, who would hold it for the rest of the conflict.

The Confederate surrender on July 4, 1863, is sometimes considered, when combined with Gen. Robert E. Lee's July 3 defeat at Gettysburg by Maj. Gen. George Meade, the turning point of the war. It cut off the states of Arkansas, Louisiana, and Texas from the rest of the Confederate States, effectively splitting the Confederacy in two for the duration of the war. The Union victory also permanently severed communication between the Trans-Mississippi Department and the balance of the Confederacy.

Folk tradition holds that the Fourth of July (Independence Day) holiday was not celebrated by Vicksburg until World War II. This claim is inaccurate, for large Independence Day celebrations were held as early as 1907.

Battlefield preservation
The works around Vicksburg are now maintained by the National Park Service as part of Vicksburg National Military Park. The park, located in Vicksburg, Mississippi, and Delta, Louisiana (flanking the Mississippi River), also commemorates the greater Vicksburg campaign which led up to the battle and includes reconstructed forts and trenches. The park includes 1,325 historic monuments and markers, 20 mi of historic trenches and earthworks, a 16 mi tour road, a 12.5 mi walking trail, two antebellum homes, 144 emplaced cannons, the restored gunboat USS Cairo (sunk on December 12, 1862, on the Yazoo River), and the Grant's Canal site, where the Union Army attempted to build a canal to let their ships bypass Confederate artillery fire.

The American Battlefield Trust and its partners have acquired and preserved 47 acres of the Vicksburg battlefield through 2021.

Existing

 * Catton, Bruce. The Centennial History of the Civil War. Vol. 3, Never Call Retreat. Garden City, NY: Doubleday, 1965. ISBN 0-671-46990-8.
 * Esposito, Vincent J. West Point Atlas of American Wars. New York: Frederick A. Praeger, 1959. . The collection of maps (without explanatory text) is available online at the West Point website.
 * Foote, Shelby. The Civil War: A Narrative. Vol. 2, Fredericksburg to Meridian. New York: Random House, 1958. ISBN 0-394-49517-9.
 * Gabel, Christopher R., Staff ride handbook for the Vicksburg Campaign, December 1862 – July 1863. Fort Leavenworth, Kan.: Combat Studies Institute Press, 2001..
 * Grabau, Warren E. Ninety-Eighty Days: A Geographer's View of the Vicksburg Campaign. Knoxville: University of Tennessee Press, 2000. ISBN 1-57233-068-6.
 * Korn, Jerry, and the Editors of Time-Life Books. War on the Mississippi: Grant's Vicksburg Campaign. Alexandria, VA: Time-Life Books, 1985. ISBN 0-8094-4744-4.
 * McPherson, James M. Battle Cry of Freedom: The Civil War Era. Oxford History of the United States. New York: Oxford University Press, 1988. ISBN 0-19-503863-0.
 * Smith, Jean Edward. Grant. New York: Simon & Schuster, 2001. ISBN 0-684-84927-5.
 * Simon, John Y., ed. The Papers of Ulysses S. Grant. Vol. 8, April 1 – July 6, 1863. Carbondale: Southern Illinois University Press, 1979. ISBN 0-8093-0884-3.
 * U.S. War Department, The War of the Rebellion: a Compilation of the Official Records of the Union and Confederate Armies. Washington, DC: U.S. Government Printing Office, 1880–1901.
 * Simon, John Y., ed. The Papers of Ulysses S. Grant. Vol. 8, April 1 – July 6, 1863. Carbondale: Southern Illinois University Press, 1979. ISBN 0-8093-0884-3.
 * U.S. War Department, The War of the Rebellion: a Compilation of the Official Records of the Union and Confederate Armies. Washington, DC: U.S. Government Printing Office, 1880–1901.